Refrigerator evaporator



April 17, 1956 R. F. HUETTL' 2,741,393

REFRIGERATOR EVAPORATOR Filed July 9, 1951 2 Sheets-Sheet l In T: l'l 35 lI-l) IN VEN TOR.

Richard l." Huezz! BYQAW 191% ,5 ATTORNEY April 17, 1956 R. F. HUETTL 2,741,898

' REFRIGERATOR EVAPORATOR Filed July 9, 1951 2 Sheets-Sheet 2 IN VEN TOR.

wwwygmg ATTORNEY United States Patent amass nurnronnAron EVAPORATOR Richard F. Huettl, St. Paul, Minn, assignor, by mesne assignments, to Whirlpool-Seeger Corporation, St. Joseph, Mich, a corporation of Delaware Application July 9, 1951, Serial No. 235,837

11 Claims. (Cl. 62 -103) This invention relates to an improvement in refrigerator evaporator and deals particularly with an evaporator useful in refrigerators equipped with automatic defrosting.

During recent years, a large percentage of the refrigerators produced have been equipped to defrost automatically from time to time. This arrangement leads to certain difficulties. It has been usual practice to provide the evaporator with horizontal surfaces which are cooled by refrigerant coils and which are designed to support items which are to be kept in a frozen condition. Frost tends to accumulate on these horizontal surfaces and accordingly when the refrigerator is defrosted, moisture tends to collect in pools on the top of these horizontal surfaces and tends to form droplets on the underside of these surfaces. When the defrosting cycle is completed, the moisture thus produced again freezes and is not eliminated from the refrigerator.

An object of the present invention lies in the provision of an evaporator which is provided with a series of vertical walls to which the refrigerant coils are secured. The horizontal walls of the evaporator are for the most part not directly connected to evaporator coils and as a result do not tend to collect frost in the same manner as the vertical walls. In order to prevent the escape of heat through the top of the evaporator enclosure a portion of the top is contacted by refrigerant coils. However, this portion of the top which is in heat transfer contact with the coils is arranged on an incline with the horizontal so that frost collecting on either the upper or lower surface thereof will drain therefrom.

A further feature of the present invention resides in the provision of a refrigerator evaporator having a substan tially horizontal lower wall designed to support food at a low temperature and which is connected to the vertical walls of the evaporator only at spaced points. Slots are provided adjacent the edges of this bottom wall of the evaporator so as to minimize the heat conduction from the unrefrigerated bottom wall to the refrigerated vertical walls. These slots also permit moisture draining down the vertical walls to escape from the evaporator chamber.

A further feature of the present invention lies in the provision of an evaporator chamber supported within the main body of the refrigerator and equipped with a downwardly and rearwardly inclined upper wall. This upper wall is in contact with refrigerant coils and is cooled thereby. However, the slant of the top wall is sufiicient to permit moisture collecting on either the upper or lower surface thereof to drain downwardly toward the rear of the refrigerator.

An added feature of the present invention lies in the provision of an evaporator having an upper surface which is substantially horizontal near its forward end and which slopes downwardly and rearwardly toward the rear of the refrigerator. Elongated transverse slots are provided near thejuncture of the inclined portion of theupperwalland the horizontal portion thereofso as 2,741,898 Patented Apr. 17, 1956 ice to minimize heat transfer between the horizontal and inclined portions of the upper wall and to assist in maintaining the horizontal portion of the upper wall at a relatively higher temperature.

An added feature of the present invention lies in the provision of an evaporator having a relatively large compartment therein for accommodating food and other materials to be held at a low temperature and a relatively smaller compartment designed to accommodate ice cube trays. Vertically spaced shelves are provided in the relatively smaller compartment to support the ice cube trays and these selves are in contact with refrigerant coils. However, these shelves are perforated to permit drainage thereofand are provided with inclined bafiles connected to the undersurface thereof so that moisture collecting on either surface may readily drain therefrom.

These and other objects and novel features of the present invention will be more clearly and fully setforth in the following specification and claims.

In the drawings forming a part of the specification:

Figure l is a cross sectional view horizontally through a refrigerator cabinet directly above the evaporator unit therein.

Figure 2 is a vertical section through a portion of the refrigerator cabinet forwardly of the evaporator unit.

Figure 3 is a sectional view through a portion of a refrigerator cabinet on one side of the evaporator unit.

Figure 4 is a sectional view through the evaporator unit and cabinet enclosing the same.

Figure 5 is a perspective view of the evaporator unit removed from the refrigerator.

The evaporator unit is indicated in general by the letter A and is designed to be enclosed within a cabinet B. The particular type of cabinet employed is not of importance in the present invention and in the form of construction illustrated is disclosed as comprising a generally rectangular cabinet having side walls and 11 and a rear wall 12. The bottom of the cabinet is not illustrated and the cabinet top is shown in general at 13. The forward side of the cabinet is open and the opening is normally closed by a door or closure 14 which is hingedly connected to the cabinet at 15 and which may be held closed by a suitable latch mechanism 16.

As is usual practice the walls, top and bottom and door of the cabinet are formed with an outer sheathing and an inner lining which are held in spaced relationship by suitable means and which ordinarily enclose insulation. The specific nature of the outer cabinet construction is not described as it is relatively unimportant in the present invention.

The evaporator unit A is best illustrated in general in Figure 5 of the drawings. As shown in this figure, the unit A includes a bottom wall 17 which is normally arranged on a generally horizontal plane. The bottom'wall 17 is connected at opposite ends to generally vertical end walls 19 and2i). Laterally extending flanges 21 and 22 are provided along the forward edges of the end Walls 19 and so as to conceal the space between the evaporator unit and the refrigerator liner. A vertical back wall 23 connects the end walls 19 and 2t! and extends upwardly from the bottom wall 17.

As indicated in Figure 4 of the drawings, the bottom wall 17 is provided with spaced slots 24 extending along the marginal edge of the bottom wall 17 adjoining the vertical wall 19. These slots 24- leave relatively narrow connecting ears 25 between the end wall 19 and the major area of the bottom panel 17 so as to reduce the conduction of heat from the bottom wall 17 to the end wall 19.

A similar row of slots 26 are provided in the bottom wall 17 along the line of connection with the vertical end wall 20. These slots 26 form relatively narrow 3 connecting strips 27 between the main part of the bottom wall and the end panel 2i so as to minimize heat conduction between these two parts.

A third series of slots 29 are provided extending along the rear wall 23 in the panel 17. These slots 29 form relatively narrow strips 36 of connection between the main part of the bottom panel 17 and the rear wall 23. This arrangement minimizes heat conduction between the bottom panel 17 and the rear wall 30.

A pair of spaced partition walls 31 and 32 extend upwardly from the bottom panel 17 parallel to the end walls 19 and 2.6 and spaced therefrom. Slots 33 are provided in the bottom wall 17 beneath the partition walls 31 and 32 to provide relatively narrow connecting strips 34 between the bottom panel 17 and the partition walls 31 and 32. This minimizes the heat conduction between the bottom panel and the partition panels 31 and 32. As indicated in Figure of the drawings, the evaporator unit A is provided with a generally rectangular top surface 35 at one end thereof between the partition panels 31 and 32 and the end wall 29. This horizontal top surface extends flush with a top strip 36 which extends from the top panel 35 to the forward end of the end wall 19. An inclined panel 37 is connected along a line of bend 39 to the top strip 36 at the forward end of the evaporator unit. This inclined panel 37 slopes downwardly and rearwardly to connect with the rear wall 23. Thus it will be seen that the end wall 19 is not entirely rectangular in form, the upper edge extending horizontally for a short distance and then inclining downwardly and rearwardly. A triangular panel 41') joins the inclined panel 37 with the horizontal panel 35 or this triangular portion 40 may comprise a part of the partition panel 31.

A series of elongated slots 51 extend across the inclined panel 37 near the line of bend 39 so as to provide relatively narrow connecting strips 42 connecting the inclined panel 37 with the horizontal panel 36. These slots reduce the heat conductivity between the horizontal panel 36 and the inclined panel 3'7.

As will be evident from the drawings, an accumrnulator 43 preferably overlies the upper surface of the inclined panel 37 near the rear edge thereof and is connected at 44 to a refrigerant coil indicated in general by the numeral 45. The refrigerant coil may be in one or more sections if desired to provide higher and lower temperature areas. In the form of construction illustrated the coil 45 includes coil loops 45 which lie outwardly of the end panel 20, coil loops 47 which lie been the partition panels 31 and 32. Coil loops 49 overlie the outer surface of the back panel 23. Refrigerant loops 50 overlie the outer surface of the end wall 19. Additional refrigerant loops 5i overlie the inclined top panel 37. One or more refrigerant loops 52 underlie the shelf 53 above the bottom panel 17 which lies between the partition walls 31 and 32 and the end wall 20. In the particular arrangement illustrated all of the refrigerant loops referred to are in series.

The space between the end wall 2% and the partition panels 31 and 32 forms an ice cube compartment in preferred form which is capable of receiving a plurality of ice cube trays. In the form illustrated a pair of additional shelves 54 and 55 are supported between the partition wall 32 and the end wall 2% in any suitable manner. Inverted V-shaped baffles 56 and 57 are supported to the undersurface of the top panel 35 and the shelf 54 respectively. These battles terminate free of the side walls 32 and of the compartment as is indicated in Figure 2. The coil loops 52 are also shown in contact with the undersurfaces of the shelves 54 and 55 as well as beneath the member 53. Ice cube trays 59 are supported by the various shelves 53, 54 and 55.

The evaporator unit is held in any suitable manner in spaced relation to the liner of the refrigerator. Figure 4 indicates spaced bolts or studs 6% which hold the evaporator unit in spaced relation to the refrigerator walls and which form a convenient means of suspending the evaporator unit. Other suitable means of suspension may be employed. It will be noted that by far the majority of the surfaces directly contacting the evaporator coil are inclined with respect to a horizontal plane. The end walls 19 and 20, as well as the rear wall 23, are in contact with portions of the coil, but obviously will permit drainage of water when the unit is defrosted. The coil portions 51 lying over the inclined panel 37 also permit drainage of Water. The partition panels 31 and 32 are similarly vertical and therefore permit any moisture collecting thereon to drain therefrom.

Of the various horizontal surfaces in the unit, the bottom panel 17, as well as the top panels 35 and 36, are in no direct contact with the refrigerant coil and therefore are not cooled to the same extent as the surfaces previously mentioned. Only the horizontal shelves 53, 54 and are refrigerated. However, the undersurfaces of these shelves which usually collect frost are in contact with the baffles such as 56 and 57 and therefore moisture collecting on these undcrsurfaces tends to drain laterally toward the sides of the ice cube compartment. In any event the horizontal refrigerator surfaces are greatly reduced in area and thus upon the defrosting of the unit the condensation which can collect or form droplets is minimized. In order to prevent the moisture from collecting upon the shelves 553, 54, and 55, these shelves are provided with holes 61 along their center lines to permit drainage from the upper surface of each shelf to the sloping baffles such as 56 and 57, thereby preventing moisture from dripping into the ice cube trays. Any moisture draining onto the battles is guided beyond the side edges of the ice cube trays so that the condensed moisture does not contaminate or join the water in the trays.

In accordance with the patent statutes, I have described the principles of construction and operation of my refrigerator evaporator, and while I have endeavored to set forth the best embodiment thereof, I desire to have it understood that obvious changes may be made within the scope of the following claims without departing from the spirit of my invention.

I claim:

1. A refrigerator including a refrigerator cabinet having a liner, an evaporator, means supporting said evaporator within said liner in spaced relation to the Walls of the cabinet and within the cabinet, said evaporator having a bottom wall, upwardly extending side walls, and a top wall, said top wall including a downwardly and rearwardly inclined portion, a spacing partition means between said side walls, and refrigerant coils adjacent said partition means and overlying the outer surfaces of the upwardly extending walls and the downwardly and rearwardly inclined portion of the upper wall, the bottom wall being substantially free of direct contact with the refrigerant coil.

2. A refrigerator including a refrigerator cabinet having a liner, an evaporator, means supporting said evaporator Within said liner in spaced relation to the walls of the cabinet and within the cabinet, said evaporator having a bottom wall, upwardly extending side walls, said bottom wall having slots therein adjacent to the upwardly extending wall to reduce the area of contact therewith, and a top wall, said top wall including a downwardly and rearwardly inclined portion, a refrigerant coil overlying the outer surfaces of the upwardly extending walls and the downwardly and rearwardly inclined portion of the upper wall, the bottom wall being substantially free of direct contact with the refrigerant coil.

3. A refrigerator including a refrigerator cabinet having a liner, an evaporator, means supporting said evaporator within said liner in spaced relation to the walls of the cabinet and within the cabinet, said evaporator having a bottom wall, upwardly extending side walls, and a top wall, said top wall including a downwardly and rearwardly inclined portion and provided with slots therein to decrease the conductive area between the in clined portion of the top wall and the remainder thereof, and a refrigerant coil overlying the outer surfaces of the upwardly extending walls and the downwardly and rearwardly inclined portion of the upper wall, the bottom wall being substantially free of direct contact with the refrigerant coil.

4. An evaporator for a refrigerator having a liner, the evaporator including a pair of end walls, a bottom wall connecting between said end walls, and a rear wall connecting said end walls, partition wall means between said end walls, said bottom wall being connected at spaced points to said walls, a top wall connecting said end walls and said rear walls, means supporting said walls within said liner, said top wall including a horizontally extending forward portion and a downwardly and rearwardly inclined portion rearwardly of said horizontal portion, and a refrigerant coil in contact with the downwardly and rearwardly inclined portion of the top wall, the bottom wall being substantially free of direct contact with the refrigerant coil.

5. An evaporator for a refrigerator having a liner, the evaporator including a pair of end walls, a bottom wall connecting between said end walls, and a rear wall connecting said end walls, a top wall connecting said end walls and said rear wall, meanssupporting said-walls with'm said liner, said top wall including a horizontally extending forward portion and a downwardly and rearwardly inclined portion rearwardly of said horizontal portion, said top wall being provided with elongated slots therein near the juncture of the horizontal portion of the top wall and the inclined portion thereof to decrease the conduction of heat therebetween, and a refrigerant coil in contact with the downwardly and rearwardly inclined portion of the top wall, the bottom wall being substantially free of direct contact with the refrigerant coil.

6. An evaporator for a refrigerator having a liner, the evaporator including a generally horizontal bottom wall, a pair of end walls secured at opposite ends thereof, a

rear wall secured to the rear end of said bottom wall and connecting said end walls, a top wall including a generally horizontal forward portion and a downwardly and rearwardly inclined portion connected to said horizontal portion and to said back wall, means supporting said walls within said liner, a refrigerant coil in contact with said inclined portion of said top wall, the horizontal portions of the top wall and the bottom wall being free of direct contact with the refrigerant coil.

7. The structure described in claim 6 and in which the coil is in contact with the end walls and rear wall.

8. An evaporator unit for a refrigerator having a liner, the evaporator including a substantially horizontal bottom wall, end walls extending upwardly from opposite ends thereof, a rear wall extending upwardly from the rear edge of said bottom wall, and a top wall including a generally horizontal partial portion extending adjacent one of said end walls and extending along the forward edge of the unit to the opposite end wall, and an inclined portion inclining downwardly and rearwardly from the said horizontal partial portion of the top wall extending across the forward edge of the unit, means supporting said walls within said liner, and a refrigerant coil in contact with said inclined wall portion and said vertical walls, and said horizontal bottom wall and said horizontal portions of said top wall being free of direct contact with said refrigerant coil.

9. The structure described in claim 8 and in which the horizontal bottom wall is connected to said end walls and said rear wall by spaced relatively narrow strips to decrease the conduction of heat therebetween.

10. An evaporator unit for a refrigerator including a bottom wall, a pair of end walls connected thereto, a rear Wall connected to the bottom wall, and a top wall connected to the rear wall and end walls, a partition panel interposed between said end walls, a series of substantially horizontal shelves arranged in spaced superimposed relation between said partition wall and one of said end walls, a refrigerant coil contacting said one end wall, said partition wall, and said shelves and inverted V-shaped baflles'supported beneath each of said shelves to direct condensation downwardly and toward said one end wall and said partition wall.

11. The structure described in claim 10 and including a series of spaced apertures through each of said shelves above said baflles.

References Cited in the file of this patent UNITED STATES PATENTS 1,991,762 Leyner Feb. 19, 1935 2,363,530 Iwashita Nov. 28, 1944 2,478,017 Shoemaker Aug. 2, 1949 2,613,510 Morton Oct. 14, 1952 2,633,003 Jordan Mar. 31, 1953 

